Band saw type bread slicing machine



May 16, 1961 M. PATTERSON BAND SAW TYPE BREAD SLICING MACHINE Filed Sept. 6, 1956 FIG.|

FIG 3 INVENTOR MOREHEAD PATTERSON ATTORNEY BAND SAW TYPE BREAD SLICING MACHINE Morehead Patterson, New York, N.Y., assignor to American Machine & Foundry Company, a corporation of New Jersey Filed Sept. 6, 1956, Ser. No. 608,291

4 Claims. (Cl. 146-88) This invention relates to band blades for cutting machines, and more particularly to band blades on bread slicing machines.

The band blade on this type machine must be twisted 90 degrees from its normal fiat position on the driving and/or supporting drums so that the edge of the blade will contact the work during the cutting run of the blade. On one common type of machine, known as a figure eight type, the blade travels in the course of a figure eight and has a 180 degree twist in it which does reduce the amount of the twisting tension necessary to support it at right angles to the work. However, in all of these machines it is necessary to provide guide lugs, more generally called fingers, to maintain the blade during its passage through the work in a straight run to make a clean cut. These guide lugs or fingers fundamentally consist of a pair of lugs having U-shaped slots through which the blade passes. One of the pair is positioned above the work and the other below the work. The guide lugs or fingers because of their frictional guiding relation to the blade have a relatively short life.

It is therefore an object of this invention to provide a blade which will increase the life of these guide lugs and concurrently the life of the blade itself.

It is an object of this invention to provide a blade having a beveled or rounded trailing edge to present a greater surface to the guide lugs or fingers at the point of greatest pressure between the lugs and the blade thereby to reduce wear on the lugs.

It is also an object of this invention to provide a similar bevel adjacent the leading edge of the blade and at the base of the teeth or scallops for the like purpose of reducing wear on the guide lugs.

It is also the purpose of this invention to so change the configuration of the blade to provide a greater area of contact between the blade and the guide lugs at the points of greatest pressure whereby less wear will result not only on the guide lugs but on the blade itself.

It is thus an object of the invention to improve the life of both the guide fingers and the blade.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention, however, both as to its organization and method of operation may be understood by reference to the following description taken in connection with the accompanying drawings, in which:

Fig. l is a partial front elevation of the cutting blade guiding and driving mechanism of a slicing machine;

Fig. 2 is an enlarged sectional plan view of a guide lug illustrating the points of contact with the rounded edges of a cutting blade passing through the same; and

Fig. 3 is an enlarged sectional plan view of a guide lug illustrating the points of contact with the beveled edges of a cutting blade passing through the same.

Referring to Fig. l, the upper and lower pulleys 12 and 14, respectively, are rotated on shafts 13 and 15, respectively. Pulleys 12 and 14 support a plurality of blades 16, two of which are here shown. One or both 1 of the pulleys 12 or 14 may be driven by means not shown or one of these pulleys may merely be an idler pulley. The sharpened edge 17 of the blade is shown by the scalloped or toothed configuration 18 which may be seen facing to the right as the blade passes over pulley 12. The blade is rotated 180 degrees so that its cutting edge 17 is facing to the left as shown in passing over the pulley 14., Intermediate the two pulleys 12 and 14 the blades are guided so that their scalloped edges are all facing in one direction by means of the upper and lower guide lugs 20. The guide lugs 20 comprise U-shaped members providing a guideway 22 that supports the blades 16 substantially transverse to the work as it is moved through the blades and between upper and lower guides 20.

' Referring more specifically to Fig. 2, the blade is shown at the angle (here exaggerated for clarity) which it assumes as it passes through a guide lug 20. It will be apparent that the greatest frictional pressure of the blade 16 on the guideway 22 is at the points a and b.

It is my invention to correct rapid wear of the lugs 20 by providing an enlarged surface contact at the points a and b. As shown in Fig. 2, the shoulder 19, formed at the base of the hollow ground cutting teeth 18, is rounded so that it will have a wider bearing contact on the guide way at the point a. Likewise the trailing edge 21 of the blade is rounded so that it will have a larger bearing contact on the guideway at the point b.

Fig. 3 shows another embodiment of the invention wherein the blade 16a is beveled at the shoulder 19' and the trailing edge 23 to increase the surface contact at points a and b, respectively.

A 7 degree bevel is suggested as optimum for commercial bread slicing machines such as are presently on the market. It is obvious, of course, that with different types of machines, particularly machines wherein the relative thickness of the blade to the width of the guideway 22 is varied, a different degree of bevel would prove more satisfactory.

It is obvious, of course, that if the blade is mounted in the figure eight shown in Fig. 1, both corners of the trailing edge and both sides of the base edge must be rounded or beveled since the blade tends to twist in an opposite direction in the upper guides than in the lower guides.

I claim:

1. In a cutting machine, the combination of an endless saw blade, means operatively connected for supporting and moving said blade, and guide means operatively supported for guiding said blade, said guide means including a pair of spaced parallel bearing surfaces, and said blade comprising a relatively flat body portion having a sharpened cutting edge and a trailing edge adapted to pass through said guide means in such a manner that said hearing surfaces engage said body portion one on each side thereof adjacent to said edges to twist and hold in a twisted relationship that portion of said blade passing through said guide means, the portions of said blade in contact with said bearing surfaces being rounded to provide substantial contact area for reducing wear of said guide means.

2. In a cutting machine, the combination of an endless saw blade, means operatively connected for supporting and moving said blade, and guide means operatively supported for guiding said blade, said guide means ineluding a pair of spaced parallel bearing surfaces, and said blade comprising a relatively flat body portion having -a sharpened cutting edge and a trailing edge adapted to pass through said guide means in such a manner that said bearing surfaces engage said body portion one on each side thereof adjacent to said edges to twist and hold in a twisted relationship that portion of said blade passing through said guide means, the portions of said blade in contact with said bearing surfaces being. beveled to provide substantial contact area for reducing wear of said guide means.

3. The combination of claim 2 in which the bevel is at an angle of approximately 7 relative to said body portion.

4. In a cutting machine, the combination of a work supporting station adapted to support the article to be cut, an endless saw blade, means :for supporting and moving said blade along a path generally having a figure eight shape, and a pair of guide elements supported on opposite sides of said Work station, said blade comprising a relatively flat body having a cutting edge and a trailing edge, each of said guide elements having a pair of spaced parallel bearing surfaces located each on a different side of said blade in such a manner that one of said bearing surfaces engages one side of the body of said blade adjacent to said cutting edge and the other of said bearing surfaces engages the other side of said body adjacent to said trailing edge to twist said blade, whereby said cutting edge passes by said work station in a path transverse to the normal path of travel of said blade, those 4 portions of said blade in engagement with said bearing surfaces being relieved to provide substantial contact area for reducing wear of said guide elements.

References Cited in the file of this patent UNITED STATES PATENTS 134,882 Hardenbergh Jan. 14, 1873 286,706 Kay Oct. '16 1883 408,669 Prescott Aug. 6,1889 825,016 Welch et a1. July 3, 1906 1,062,358 Ranger May 20, 1913 2,064,261 How et a1. Dec. 15, 1936 2,225,600 Kottmann Dec. 17, 1940 2,250,324 Baker July 22, 1941 2,331,157 Arey Oct. 5, 1943 2,646,094 Russell Oct. 5, 1943 2,765,008 Hawkins Oct. 2, 1956 2,771,918 Watson Nov. 27, 1956 FOREIGN PATENTS 886,843 France Oct. 26, 1943 592,234 Great Britain Sept. 11, 1947 

